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New Phytologist is a leading world journal, publishing original research
papers on all aspects of the plant sciences. It publishes also a prestigious
series of invited reviews, Tansley Reviews, named after Sir Arthur
Tansley who founded the journal in 1902. In addition, submitted reviews are
published as well as a Forum section containing short articles on current issues
in the plant sciences. The journal is non-profit making. The Trustees of the
registered charity ensure that income is used solely to support the plant sciences.
JSTOR provides a digital archive of the print version of New Phytologist.
The electronic version of New Phytologist is available at http://www.interscience.wiley.com.
Authorized users may be able to access the full text articles at this site.

The "moving wall" represents the time period between the last issue
available in JSTOR and the most recently published issue of a journal.
Moving walls are generally represented in years. In rare instances, a
publisher has elected to have a "zero" moving wall, so their current
issues are available in JSTOR shortly after publication.
Note: In calculating the moving wall, the current year is not counted.
For example, if the current year is 2008 and a journal has a 5 year
moving wall, articles from the year 2002 are available.

Terms Related to the Moving Wall

Fixed walls: Journals with no new volumes being added to the archive.

Absorbed: Journals that are combined with another title.

Complete: Journals that are no longer published or that have been
combined with another title.

Abstract

The wood (xylem) in a living tree is protected from microbial attack by the secondary plant surface (periderm and rhytidome), which provides an effective barrier preventing the entry of most potential pathogens, and by constitutive and induced defence mechanisms in the bark (cortex and phloem). Although a few pathogens are able to penetrate these outer tissues directly, most xylem pathogens gain entry through wounds that expose this tissue and render it more vulnerable to attack. In functional sapwood, microbial colonization might be restricted by active defence mechanisms, or by passive microenvironmental restriction consequent upon the high water content and low availability of O2 in healthy conductive xylem. These factors are not mutually exclusive: indeed, they may operate in concert in many host-pathogen interactions. Sapwood lesions made by wood-decaying fungi are characteristically bounded by multicellular walls or barrier zones (compartmentalization wall 4 barriers and reaction zones (column boundary layers)), which may function both as inhibitory or degradation-resistant barriers to further pathogen spread, and as seals to maintain xylem function and prevent the drying and aeration that could predispose to further infection. A range of putative antimicrobial defence mechanisms contributing to the effectiveness of such barriers has been identified in sapwood tissues. This includes cell wall alterations, constitutive and induced antimicrobial compounds, necrotic responses of living cells and the deposition of gummy materials, often resinous or polyphenolic, at the host-pathogen interface. Nutritional, environmental and anatomical features of living wood might also contribute to pathogen restriction. Although there might be differences in detail, the defences operating in gymnosperms and angiosperms are generally similar. Defence responses against a variety of pathogen categories also have much in common. Dynamic studies are crucial in elucidating the roles of the various components of the host-pathogen interaction in the wood of living trees. A model for the protection and defence of xylem tissues in woody angiosperms is suggested, based largely upon results from dynamic studies of host-pathogen interactions in the wood of sycamore (Acer pseudoplatanus L.).